The present invention concerns sprinkler heads for fire extinguisher systems for buildings and the like, and more particularly concerns a sprinkler head configured to facilitate assembly and reduce manufacturing costs.
Sprinkler heads are used in fire extinguisher systems for buildings to automatically dispense water droplets in case of a fire. Historically, the sprinkler heads include a solid metal base connected to a pressurized supply of water, and a frangible bulb for holding a seal over a water outlet in the base. The frangible bulb breaks when it senses a predetermined temperature, thus allowing water from the pressurized source of water to push away the seal and flow from the base onto the fire. The base is typically carefully machined to minimize dimensional variation and irregularities on the base so that the frangible bulb is not over-stressed or unevenly stressed by engagement with the base after assembly, which stresses can cause the frangible bulb to prematurely fail. However, the frangible bulb includes dimensional variations making it difficult to adequately control assembly tolerances even if the dimensional variation in the base is controlled. One solution to this problem is to include a bulb-supporting adjustment screw on the base or on an integral frame supported on the base so that dimensional variation in the frangible bulb and in the base can be taken up by the adjustment screw. For example, see FIG. 1 in the attached drawings. However, the adjustment screw and the structure on the base for receiving same add cost and complexity to the sprinkler head. Further, machining the base adds costly additional manufacturing steps, and results in scrap material and waste during the machining process.
Many known sprinkler heads include individual parts that are chrome-plated or otherwise surface treated to prevent corrosion and/or improve appearance. However, attachment of one part to another by standard welding techniques disrupts the chrome plating or other commonly used surface treatments such that the parts are again subject to corrosion after assembly by welding. More expensive noncorroding materials can be used; however, even if the additional cost is justifiable, standard welding techniques may adversely affect the appearance of these parts.
Thus, a sprinkler head solving the aforementioned problems is desired.